62 Bulletin 233. 



striking contrast to the well defined, one-brooded life of its near relative, the 

 elm sawfly, herein discussed. 



The insect hibernates as a larva in the soil near the surface in its brown, 

 papery cocoon, the transformation to the pupa occurring in May. Thirty-one 

 cocoons were found in an area of only four square inches under a small tree 

 last May. 



Remedial suggestions. — During the past season I have tested a simple, 

 practicable, and effective method for controlling this insect. Finding that it 

 hibernates within an inch from the surface of the soil, I buried several cocoons 

 at depths of 2 , 4 and 6 inches. But very few of the flies emerged from any 

 of the buried cocoons. A thin layer of the sod beneath the infested trees 

 was at once removed and should have been carried away promptly, but it was 

 delayed until many of the flies emerged. Thus the infestation was not checked 

 so completely as it should have been, but the trees are not nearly so badly 

 injured this year as in 1904. 



By promptly removing about one or two inches of the sod or soil from 

 beneath trees infested by the insect about May ist, and carrying it to a con- 

 siderable distance or burying it, this insect can be easily and effectively con- 

 trolled. By thus preventing the emergence of the spring brood of sawflies, 

 the development of succeeding broods is stopped. In many cases, it would 

 doubtless be practicable to simply spade under the sod to a depth of six or eight 

 inches, and pack it down hard. Care should be taken to remove the sod over 

 an area extending a foot or two beyond the circle bounding the points to which 

 the longest limbs reach. Thorough and prompt burying of the cocoons n 

 this manner about May ist, will control this sawfly miner and preserve the 

 beauty of this desirable European tree. 



